Actuator Tilt Interposer For Within-Row Lapping Mount Tool For Magnetic Recording Read-Write Heads

ABSTRACT

A lapping tool assembly includes a mount tool and an interposer structure interposed between actuators and the mount tool, where the interposer includes interposer pins reactively coupled with the actuators such that each interposer pin is configured to receive a translational force from a corresponding actuator and to transmit the force to a corresponding actuation pin of the mount tool. The interposer may include a zero z-axis shift flexure system, and/or a z-axis decoupling flexure system, and/or alignment features, for accurately transmitting the actuation forces to the mount tool, while inhibiting affecting other portions of the mount tool.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of and claims the benefit ofpriority to pending U.S. patent application Ser. No. 15/190,859 filed onJun. 23, 2016, the entire content of which is incorporated by referencefor all purposes as if fully set forth herein.

FIELD OF EMBODIMENTS

Embodiments of the invention may relate generally to magnetic recordingdevices and more particularly to controlling the element stripe heightand wedge angle within a row-bar.

BACKGROUND

A hard-disk drive (HDD) is a non-volatile storage device that is housedin a protective enclosure and stores digitally encoded data on one ormore circular disks having magnetic surfaces. When an HDD is inoperation, each magnetic-recording disk is rapidly rotated by a spindlesystem. Data is read from and written to a magnetic-recording disk usinga read-write head that is positioned over a specific location of a diskby an actuator. A read-write head uses a magnetic field to read datafrom and write data to the surface of a magnetic-recording disk. A writehead makes use of the electricity flowing through a coil, which producesa magnetic field. Electrical pulses are sent to the write head, withdifferent patterns of positive and negative currents. The current in thecoil of the write head induces a magnetic field across the gap betweenthe head and the magnetic disk, which in turn magnetizes a small area onthe recording medium.

High volume magnetic thin film head slider fabrication involves highprecision subtractive machining performed in discrete material removalsteps. Slider processing starts with a completed thin film head waferconsisting of 40,000 or more devices, and is completed when all thedevices are individuated and meet numerous and stringent specifications.Each individual device ultimately becomes a read-write head (e.g.,Perpendicular Magnetic Recording (PMR) heads) for flying over a spinningdisk.

Increasing areal density (a measure of the quantity of information bitsthat can be stored on a given area of disk surface) is one of theever-present goals of hard disk drive design evolution, and has led tothe necessary development and implementation of various means forreducing the disk area needed to record a bit of information. Precisecontrol of the critical dimensions of a read head element and a writehead element, by way of machining and lapping, are commonly practicedand are a necessity of manufacturing. Of continued importance is thealignment of the read and write portions of the head relative to eachother. For optimum yield, performance and stability, precise dimensionalcontrol over both the reader and/or writer elements is desirable.

For example, process improvements regarding the magnetic core width(MCW) (as well as the magnetic erase width (MEW), magnetic write width(MWW), magnetic interference width (MIW), and other related magneticcore measures) would benefit areal density because the MCW effectivelydetermines the width of a magnetic bit recorded by the write head.Furthermore, the single largest contributor to the overall MCW sigma istypically the “within row-bar” sigma. Even though manufacturingprocesses are developed to produce read-write heads having MCW as closeas possible to a desired MCW for the system, some thin-film and othermanufacturing processes (e.g., lithography, etching, rough lapping,material elasticity, etc.) experience inherent variations that make itquite challenging to achieve the desired MCW for every read-write headmanufactured.

Any approaches described in this section are approaches that could bepursued, but not necessarily approaches that have been previouslyconceived or pursued. Therefore, unless otherwise indicated, it shouldnot be assumed that any of the approaches described in this sectionqualify as prior art merely by virtue of their inclusion in thissection.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated by way of example, and not by way oflimitation, in the figures of the accompanying drawings and in whichlike reference numerals refer to similar elements and in which:

FIG. 1 is a plan view illustrating a hard disk drive (HDD), according toan embodiment;

FIG. 2 is an exploded perspective view illustrating a wafer of headsliders in various stages of processing, according to an embodiment;

FIG. 2A is a perspective view illustrating a read-write transducer,according to an embodiment;

FIG. 3 is a diagram illustrating a wedge angle lapping (WAL) process;

FIGS. 4A, 4B are diagrams illustrating a rigid bond WA lapping process;

FIG. 5 is a bottom side perspective view illustrating a lapping tool,according to an embodiment;

FIG. 6 is a bottom front perspective view illustrating the lapping toolof FIG. 5, according to an embodiment;

FIG. 7 is a cross-sectional side view illustrating the lapping tool ofFIGS. 5-6, according to an embodiment;

FIG. 7A is a cross-sectional side view illustrating a fixture of thelapping tool of FIG. 7, according to an embodiment;

FIG. 8 is a flow diagram illustrating a method for lapping a row-bar ofhead sliders, according to an embodiment;

FIGS. 9A, 9B are diagrams illustrating a “soft” bond WA lapping process,according to an embodiment;

FIG. 10A is a front side perspective view illustrating a lapping mounttool, according to an embodiment;

FIG. 10B is a front top perspective view illustrating the lapping mounttool of FIG. 10A, according to an embodiment;

FIG. 10C is a bottom side perspective view illustrating the lappingmount tool of FIG. 10A, according to an embodiment;

FIG. 11 is a cross-sectional side view illustrating the lapping mounttool of FIGS. 10A-10C, according to an embodiment;

FIG. 12A is an exploded top side perspective view illustrating a portionof a lapping tool assembly, according to an embodiment;

FIG. 12B is a top side perspective view illustrating a portion of thelapping tool assembly of FIG. 12A, according to an embodiment;

FIG. 13A is an exploded front side perspective view illustrating aportion of a lapping tool assembly, according to an embodiment;

FIG. 13B is an exploded side perspective view illustrating a portion ofthe lapping tool assembly of FIG. 13A, according to an embodiment;

FIG. 14 is a flow diagram illustrating a method for lapping a row-bar ofhead sliders, according to an embodiment;

FIG. 15A is a side perspective view illustrating a lapping tool assemblyincluding an actuator tilt interposer, according to an embodiment;

FIG. 15B is a side perspective view illustrating a portion of thelapping tool assembly of FIG. 15A, according to an embodiment;

FIG. 16 is a cross-sectional side view of the actuator tilt interposerof FIG. 15A, according to an embodiment;

FIG. 17 is a cross-sectional side view of the lapping tool assembly ofFIG. 15A, according to an embodiment;

FIG. 18 is a side perspective view of a pre-aligner of the actuator tiltinterposer of FIG. 15A, according to an embodiment; and

FIG. 19 is a flow diagram illustrating a method for applying actuationforces to a lapping mount tool for lapping a row-bar of magnetic sensordevices, according to an embodiment.

DETAILED DESCRIPTION

Approaches to lapping a row-bar of magnetic sensors, utilizing a lappingtool assembly, are described. In the following description, for thepurposes of explanation, numerous specific details are set forth inorder to provide a thorough understanding of the embodiments of theinvention described herein. It will be apparent, however, that theembodiments of the invention described herein may be practiced withoutthese specific details. In other instances, well-known structures anddevices are shown in block diagram form in order to avoid unnecessarilyobscuring the embodiments of the invention described herein.

Physical Description of Illustrative Operating Environments

Embodiments may be used in the context of a read-write head for adigital data storage device such as a hard disk drive (HDD). Thus, inaccordance with an embodiment, a plan view illustrating an HDD 100 isshown in FIG. 1 to illustrate an exemplary operating context.

FIG. 1 illustrates the functional arrangement of components of the HDD100 including a slider 110 b that includes a magnetic read-write head110 a. Collectively, slider 110 b and head 110 a may be referred to as ahead slider. The HDD 100 includes at least one head gimbal assembly(HGA) 110 including the head slider, a lead suspension 110 c attached tothe head slider typically via a flexure, and a load beam 110 d attachedto the lead suspension 110 c. The HDD 100 also includes at least onerecording medium 120 rotatably mounted on a spindle 124 and a drivemotor (not visible) attached to the spindle 124 for rotating the medium120. The read-write head 110 a, which may also be referred to as atransducer, includes a write element and a read element for respectivelywriting and reading information stored on the medium 120 of the HDD 100.The medium 120 or a plurality of disk media may be affixed to thespindle 124 with a disk clamp 128.

The HDD 100 further includes an arm 132 attached to the HGA 110, acarriage 134, a voice-coil motor (VCM) that includes an armature 136including a voice coil 140 attached to the carriage 134 and a stator 144including a voice-coil magnet (not visible). The armature 136 of the VCMis attached to the carriage 134 and is configured to move the arm 132and the HGA 110 to access portions of the medium 120, all collectivelymounted on a pivot shaft 148 with an interposed pivot bearing assembly152. In the case of an HDD having multiple disks, the carriage 134 maybe referred to as an “E-block,” or comb, because the carriage isarranged to carry a ganged array of arms that gives it the appearance ofa comb.

An assembly comprising a head gimbal assembly (e.g., HGA 110) includinga flexure to which the head slider is coupled, an actuator arm (e.g.,arm 132) and/or load beam to which the flexure is coupled, and anactuator (e.g., the VCM) to which the actuator arm is coupled, may becollectively referred to as a head stack assembly (HSA). An HSA may,however, include more or fewer components than those described. Forexample, an HSA may refer to an assembly that further includeselectrical interconnection components. Generally, an HSA is the assemblyconfigured to move the head slider to access portions of the medium 120for read and write operations.

With further reference to FIG. 1, electrical signals (e.g., current tothe voice coil 140 of the VCM) comprising a write signal to and a readsignal from the head 110 a, are transmitted by a flexible cable assembly(FCA) 156 (or “flex cable”). Interconnection between the flex cable 156and the head 110 a may include an arm-electronics (AE) module 160, whichmay have an on-board pre-amplifier for the read signal, as well as otherread-channel and write-channel electronic components. The AE module 160may be attached to the carriage 134 as shown. The flex cable 156 may becoupled to an electrical-connector block 164, which provides electricalcommunication, in some configurations, through an electricalfeed-through provided by an HDD housing 168. The HDD housing 168 (or“enclosure base” or simply “base”), in conjunction with an HDD cover,provides a semi-sealed (or hermetically sealed, in some configurations)protective enclosure for the information storage components of the HDD100.

Other electronic components, including a disk controller and servoelectronics including a digital-signal processor (DSP), provideelectrical signals to the drive motor, the voice coil 140 of the VCM andthe head 110 a of the HGA 110. The electrical signal provided to thedrive motor enables the drive motor to spin providing a torque to thespindle 124 which is in turn transmitted to the medium 120 that isaffixed to the spindle 124. As a result, the medium 120 spins in adirection 172. The spinning medium 120 creates a cushion of air thatacts as an air-bearing on which the air-bearing surface (ABS) of theslider 110 b rides so that the slider 110 b flies above the surface ofthe medium 120 without making contact with a thin magnetic-recordinglayer in which information is recorded. Similarly in an HDD in which alighter-than-air gas is utilized, such as helium for a non-limitingexample, the spinning medium 120 creates a cushion of gas that acts as agas or fluid bearing on which the slider 110 b rides.

The electrical signal provided to the voice coil 140 of the VCM enablesthe head 110 a of the HGA 110 to access a track 176 on which informationis recorded. Thus, the armature 136 of the VCM swings through an arc180, which enables the head 110 a of the HGA 110 to access varioustracks on the medium 120. Information is stored on the medium 120 in aplurality of radially nested tracks arranged in sectors on the medium120, such as sector 184. Correspondingly, each track is composed of aplurality of sectored track portions (or “track sector”) such assectored track portion 188. Each sectored track portion 188 may includerecorded information, and a header containing error correction codeinformation and a servo-burst-signal pattern, such as anABCD-servo-burst-signal pattern, which is information that identifiesthe track 176. In accessing the track 176, the read element of the head110 a of the HGA 110 reads the servo-burst-signal pattern, whichprovides a position-error-signal (PES) to the servo electronics, whichcontrols the electrical signal provided to the voice coil 140 of theVCM, thereby enabling the head 110 a to follow the track 176. Uponfinding the track 176 and identifying a particular sectored trackportion 188, the head 110 a either reads information from the track 176or writes information to the track 176 depending on instructionsreceived by the disk controller from an external agent, for example, amicroprocessor of a computer system.

An HDD's electronic architecture comprises numerous electroniccomponents for performing their respective functions for operation of anHDD, such as a hard disk controller (“HDC”), an interface controller, anarm electronics module, a data channel, a motor driver, a servoprocessor, buffer memory, etc. Two or more of such components may becombined on a single integrated circuit board referred to as a “systemon a chip” (“SOC”). Several, if not all, of such electronic componentsare typically arranged on a printed circuit board that is coupled to thebottom side of an HDD, such as to HDD housing 168.

References herein to a hard disk drive, such as HDD 100 illustrated anddescribed in reference to FIG. 1, may encompass an information storagedevice that is at times referred to as a “hybrid drive”. A hybrid driverefers generally to a storage device having functionality of both atraditional HDD (see, e.g., HDD 100) combined with solid-state storagedevice (SSD) using non-volatile memory, such as flash or othersolid-state (e.g., integrated circuits) memory, which is electricallyerasable and programmable. As operation, management and control of thedifferent types of storage media typically differ, the solid-stateportion of a hybrid drive may include its own corresponding controllerfunctionality, which may be integrated into a single controller alongwith the HDD functionality. A hybrid drive may be architected andconfigured to operate and to utilize the solid-state portion in a numberof ways, such as, for non-limiting examples, by using the solid-statememory as cache memory, for storing frequently-accessed data, forstoring I/O intensive data, and the like. Further, a hybrid drive may bearchitected and configured essentially as two storage devices in asingle enclosure, i.e., a traditional HDD and an SSD, with either one ormultiple interfaces for host connection.

Introduction

The term “substantially” will be understood to describe a feature thatis largely or nearly structured, configured, dimensioned, etc., but withwhich manufacturing tolerances and the like may in practice result in asituation in which the structure, configuration, dimension, etc. is notalways or necessarily precisely as stated. For example, describing astructure as “substantially vertical” would assign that term its plainmeaning, such that the sidewall is vertical for all practical purposesbut may not be precisely at 90 degrees.

As mentioned, the largest contributor to the overall magnetic core width(MCW) sigma is typically the “within row-bar” sigma, and even thoughmanufacturing processes are developed to produce read-write heads havingan MCW as close as possible to a target MCW, some thin-film processesexperience inherent variations that make it an ongoing challenge toachieve the target MCW for every head manufactured.

Furthermore, high-volume magnetic thin film head slider fabricationinvolves high precision subtractive machining performed in discretematerial removal steps. Slider processing starts with a completed thinfilm head wafer consisting of 40,000 or more devices, and is completedwhen all the devices are individuated and meet numerous and stringentspecifications. The individual devices ultimately become head slidershousing a read-write head. Therefore, precise control of the readerdimension and of the alignment of the reader and writer relative to eachother are critical components of the read-write head fabricationprocess, in order to achieve optimum yield, performance, and stability.In order to achieve ideal dimensions for each individual read-writehead, one might choose to process each head slider individually.However, that approach is hardly feasible from a practicalmanufacturability standpoint because, for example, it results in asignificantly more complex, inefficient, and costly head sliderfabrication process.

FIG. 2 is an exploded perspective view illustrating a wafer of headsliders in various stages of processing, and FIG. 2A is a perspectiveview illustrating a read-write transducer, both according to anembodiment. FIG. 2 depicts a wafer 202, comprising a matrix ofunfinished head sliders having unfinished read-write transducers (see,e.g., FIG. 2A) deposited on a substrate 203, for which AlTiC is commonlyused. The matrix of sliders is typically processed in batches, i.e.,subsets of the wafer, historically referred to as “quads” and now attimes referred to as “chunks” or “blocks”. A block of unfinished headsliders, block 204, comprises multiple rows 206 a-206 n (or “row-bars”)of unfinished head sliders, where n represents a number of row-bars perblock 204 that may vary from implementation to implementation. Each row206 a-206 n comprises multiple head sliders 208 a-208 m, where mrepresents a number of head sliders per row 206 a-206 n that may varyfrom implementation to implementation.

With reference to FIG. 2A, read-write transducer 210 comprises a writerelement 212 (or simply “writer 212”) and a corresponding coil 216. Writeheads make use of the electricity flowing through a coil such as coil216 to produce a magnetic field. Electrical pulses are sent to the writehead, with different patterns of positive and negative currents, wherethe current in the coil of the write head induces a magnetic fieldacross the gap between the head and the magnetic disk, which in turnmagnetizes a small area on the recording medium. A writer such as writer212 has a corresponding flare point 213, which is the distance between(a) the end of the main pole (i.e., the end of the pole tip 220) of thewriter and (b) the point 221 at which the pole tip 220 flares down toits smallest cross-section. The flare point 213 is commonly considered acritical dimension associated with a magnetic writer such as writer 212.

Continuing with FIG. 2A, read-write transducer 210 further comprises areader element 214 (or simply “reader 214”) having a correspondingstripe height 215, which is also considered a critical dimensionassociated with a magnetic reader such as reader 214. The flare point213 of the writer 212 and the stripe height 215 of the reader 214 arecommonly controlled in fabrication by, but not limited to, a “rough lap”process referred to as wedge angle lapping (“WAL”), which is describedin more detail herein (such as in reference to FIG. 3).

Read-write transducers such as transducer 210 are further associatedwith a reader-writer offset 217 (or “read-write offset”, or “RWO”),which is the distance between a certain point or surface of the reader214 and a certain point or surface of the writer 212, in what isdepicted as the y-direction. The RWO 217 is designed into the read-writetransducer 210. However, uncontrollable (and undesirable) offsetsbetween the writer 212 and the reader 214 may occur during wafer 202fabrication, which may cause a linear and/or angular offset that mayvary along a row in what is depicted as the x-direction. Any such offsetis largely due to the fact that the writer 212 and the reader 214 aredeposited in different thin-film layers and, therefore, is due tomanufacturing process limitations. For example, the writer 212 and thereader 214 may not always line up precisely relative to the air bearingsurface and/or relative to each other because of the challengesassociated with exposing different masks having different patterns atdifferent deposition layers, in nanometer-scale manufacturing processes.

Consequently, the RWO fabricated at the wafer level may not be preciselythe target RWO. Hence, the aforementioned WAL (or “RWO angle”) processis typically employed to align a row-bar RWO more closely to the targetRWO. However, the aforementioned rough lapping WAL process can typicallyonly reach a level of correction around 5 nm, and is typically applied“per row-bar” rather than “per slider”. Thus, a finer, more preciselapping procedure could be considered useful.

Head Slider Fabrication Processes-Generally

A typical head slider fabrication process flow may include thefollowing: a wafer (e.g., wafer 202 of FIG. 2) fabrication process,which includes deposition of the reader and writer elements (e.g.,reader 214 and writer 212 of FIG. 2A), followed by block (or “quad”)slicing to remove a block (e.g., block 204 of FIG. 2) of unfinishedsliders from the wafer. An outer row (e.g., row 206 a of FIG. 2) ofsliders (e.g., head sliders 208 a-208 m of FIG. 2) from the block maythen be rough lapped (e.g., wedge angle lapped) in order to fabricateclose to the desired reader and writer dimensions (e.g., flare point 213and stripe height 215 of FIG. 2A), and then the outer rough-lapped row(e.g., row 206 a) sliced from the block (e.g., block 204). From there,the row may be further lapped, such as “back-lapped” to form theflexure-side surface opposing the air bearing surface (ABS), and“fine-lapped” (or “final lapped”) to further refine the ABS surface.This then may lead to overcoating, and rail etching, etc. of the ABSsurface to form the final air bearing or flying surface, at which pointeach head slider (e.g., head sliders 208 a-208 m) may be diced or partedfrom the row to individuate each finished head slider, whereby it canthen be coupled with a flexure, assembled into a head-gimbal assembly(HGA), and so on.

Wedge Angle Lapping

As discussed, the flare point 213 (FIG. 2A) of the writer 212 (FIG. 2A)and the stripe height 215 (FIG. 2A) of the reader 214 (FIG. 2A) arecommonly controlled in fabrication by, but not limited to, a roughlapping process referred to as wedge angle lapping (“WAL”). With“passive WAL control”, a row-bar is lapped to a predetermined wedgeangle (“WA”), often based upon off-line electrical test measurements,whereby the WA is controlled by lapping to a physical target angle.Alternatively, with “active WAL control”, the row-bar is served orcontrolled to a desired RWO, based on resistance-based feedback (e.g.,from use of electronic lapping guides, or “ELGs”, associated with thereader and/or writer elements). In both cases, an average or median WAis targeted for the entire row-bar, without individual control of thehead sliders within the row-bar.

FIG. 3 is a diagram illustrating a wedge angle lapping (WAL) process,such as at a rough lap stage. The left-hand diagram of FIG. 3 depicts ahead slider 302 before air bearing surface (“ABS”) rough lapping. Thereader 214 and corresponding desired stripe height 215 are depicted, thelapping of which as previously mentioned is typically controlled via aresistance-based feedback mechanism, and the writer 212 andcorresponding resultant flare point 213 are also depicted. A dashed lineillustrates the desired final ABS, which is achieved by lapping the ABSside of the head slider 302 at a wedge angle 303.

Thus, with reference to the right-hand side diagram of FIG. 3, ABSlapping may be performed on head slider 302 using a lapping fixture 304and a lapping plate 306 (e.g., commonly diamond-encrusted and/oraccompanied by a diamond slurry), depicted in simplified form. Thefixture 304 is set such that the lapping plate 306 operates to lap thehead slider 302 at a wedge angle 303 until target reader 214 and writer212 dimensions are ultimately reached, thereby achieving read-write headhaving at least the desired stripe height 215 for this particularportion of the head slider fabrication process.

Wedge angle lapping is typically performed at a certain predeterminedwedge angle on an entire row-bar of sliders, such as any of row 206a-206 n (FIG. 2). Thus, each of the sliders 208 a-208 m (FIG. 2) withina given row is rough lapped at the same wedge angle, such as wedge angle303 (FIG. 3). However, as previously mentioned, an undesirable offset(s)between the writer 212 (FIG. 2A) and the reader 214 (FIG. 2A) may occurduring wafer 202 (FIG. 2) fabrication, which may cause a linear and/orangular offset in one or more directions. Furthermore, such an offset(s)corresponding to the Titer 212 and the reader 214 may not be constantalong the length (x-direction) of any given row (e.g., row 206 a) ofhead sliders, nor across multiple rows (e.g., rows 206 a-206 n) from ablock (e.g., block 204 of FIG. 2). Again, therein lies a reason thatprocessing of head sliders individually, if practically feasible, may beconsidered desirable.

FIGS. 4A, 4B are diagrams illustrating a rigid bond WA lapping process,which may be applicable to a scenario as depicted in FIG. 3. FIG. 4Adepicts a series of “snapshots” (with each snapshot separated by avertical dashed line) of a rough lap WAL process, in which an unfinishedhead slider 402 is temporarily bonded to a rigid tooling fixture 404using a rigid adhesive bond 403. In the top portion of FIG. 4A, it isappreciated that the head slider 402 is progressively lapped at a firstwedge angle α, using a lapping plate 406, thus fabricating a head slider402-1 depicted as having a first quadrilateral polygon shape. Lapping atthe wedge angle α may be with the purpose of achieving a particulartarget stripe height for the reader (such as stripe height 215 forreader 214 of FIG. 2A). With reference to FIG. 4B, it is appreciatedthat at the constant wedge angle α, the progression of head slider 402material removal is uniform (i.e., at a constant angle) as lappingprogresses through the WAL process to reach head slider 402-1.

In the bottom portion of FIGS. 4A, 4BA, it is appreciated that the headslider 402-1 is progressively lapped at a second wedge angle β,continuing to use the lapping plate 406, thus fabricating a head slider402-2 depicted as having a second quadrilateral polygon shape. Thislapping to the constant wedge angle β is similarly uniform as lappingprogresses through the WAL process to reach head slider 402-2. It isnoteworthy that, in current practice, adjustment of the wedge angle cantypically only be made one or two times during the rough lap WAL processdepicted in FIGS. 4A, 4B. Furthermore, use of constant wedge angles,even if adjusted once or twice, may produces a facet(s) in the headslider (best depicted in head slider 402-1). Still further, it isnoteworthy that this rough lap WAL process is commonly employed bytargeting a reader element stripe height (such as stripe height 215 forreader 214 of FIG. 3), and obtaining lapping feedback via a reader orwriter ELG, while the writer element flare point (such as flare point213 for writer 212 of FIG. 3) and the RWO 217 (FIG. 2) are relativelyuncontrolled.

Lapping Tool for within-Row Wedge Angle Lapping

FIG. 5 is a bottom side perspective view illustrating a lapping tool,and FIG. 6 is a bottom front perspective view illustrating the lappingtool of FIG. 5, both according to embodiments. Lapping tool 500comprises a box structure 502 that, according to an embodiment, isrotatable and/or flexible. The box structure 502 includes a front side504 housing a plurality of force pins 505 that are generallytranslatable in a z-direction, and a back wall 506.

The lapping tool 500 further comprises a fixture 508 for holding arow-bar 206 of magnetic read-write head sliders, such that each of theplurality of force pins 505 is positioned to apply a force to acorresponding head slider of the row-bar 206. The lapping tool 500further comprises a second back wall 510 a distance from the back wall506 of the box structure 502, and at least two flexible wedge angle (WA)flexures 512 a, 512 b (three depicted, along with WA flexure 512 c)interconnecting the back wall 506 of the box structure 502 and thesecond back wall 510. Notably, the WA flexures 512 a, 512 b, 512 c“virtually” intersect at, and therefore define, an axis of rotationabout an x-axis associated with the row-bar 206 (depicted and describedin more detail in reference to FIGS. 7, 7A). Hence, in response toactuation, and based on the virtual intersection of the WA flexures 512a, 512 b, 512 c, each force pin 505 applies a torque to itscorresponding head slider about the axis of rotation defined by thevirtual intersection of the WA flexures 512 a, 512 b, 512 c.

Based on the foregoing interacting structures of lapping tool 500, anindependent and variable wedge angle (relative to the y-axis direction)can be set for each head slider (e.g., head slider 208 a-208 m of FIG.2) of the row-bar 206, for lapping to a respective target wedge angle.In effect, the plurality of force pins 505, in response to actuation,collectively twists the row-bar 206 to concurrently set each head sliderof the row-bar 206 for concurrent lapping to its respective target wedgeangle.

According to an embodiment, the lapping tool 500 further comprises acompliant elastomer 516 between each force pin 505 and its correspondinghead slider (e.g., head slider 208 a-208 m of FIG. 2) of the row-bar206, to transfer a y-direction pressure gradient (e.g., pressuregradient 904 a of FIG. 9A) corresponding to the torque from the forcepin 505 to the corresponding head slider 208 a-208 m. As such, thematerial removal associated with each head slider 208 a-208 m due tolapping corresponds to the pressure gradient 904 a applied to eachrespective head slider 208 a-208 m.

According to an embodiment, the material of elastomer 516 has a Shore Ahardness in a range of 10-90 durometer, which is found suitable for itsintended purpose. For example, use of a compliant elastomer 516 (ratherthan a rigid bond such as rigid adhesive bond 403 of FIG. 4A), fornon-limiting examples, a silicon or polyurethane rubber (e.g., 0.05-1.5mm thick, a range found suitable for its intended purpose), effectivelyeliminates the action of the head slider lifting off the lapping plateand associated faceting of the head slider which may occur with therigid bond of FIG. 4A. Furthermore, the thicker the elastomer 516, thesofter the cushion it provides between the force pins 505 and the headsliders 208 a-208 m (FIG. 2) and, therefore, finer control of thepressure gradient 904 a across each head slider 208 a-208 m is achieved.That is, the response corresponding to actuation of the force pins 505and their effect on the head sliders 208 a-208 m is effectivelydampened. Likewise, the harder the elastomer 516, the more rapid theresponse corresponding to actuation of the force pins 505 and theireffect on the head sliders 208 a-208 m (i.e., the response is lessdampened and finer actuation control for more gradual change should beprovided). Thus, the effective resolution of the pressure gradient 904 aacross each head slider can vary from implementation to implementation,based on the choice of material used for the compliant elastomer 516.

The lapping tool 500 further comprises at least two flexible stripeheight (SH) flexures 514 a, 514 b interconnecting the front side 504 andthe back wall 506 of the box structure 502. In view of the structuralsupport provided by the SH flexures 514 a, 514 b to the overall boxstructure 502, each force pin 505 can apply a z-directional force to itscorresponding head slider (e.g., head slider 208 a-208 m of FIG. 2) ofthe row-bar 206, for lapping to a respective reader target stripe height(such as stripe height 215 for reader 214 of FIG. 2A). Thus, based onthe foregoing interacting structures of lapping tool 500, an independentreader target stripe height (relative to the z-axis) can be set for eachhead slider of the row-bar 206, for lapping to its respective targetstripe height.

Lapping Tool Wedge Angle Flexures

FIG. 7 is a cross-sectional side view illustrating the lapping tool ofFIGS. 5-6, and FIG. 7A is a cross-sectional side view illustrating afixture of the lapping tool of FIG. 7, both according to embodiments.FIGS. 7 and 7A are referenced to describe in more detail the WA flexures512 a, 512 b, 512 c (FIGS. 5-6).

FIG. 7 illustrates the lapping tool 500 and constituent components,according to embodiments described in reference to FIGS. 5-6. FIGS. 7and 7A further illustrate that the at least two wedge angle (WA)flexures 512 a, 512 b (and optional 512 c), which interconnect the backwall 506 of the box structure 502 and the second back wall 510, arepositioned and configured such that the WA flexures 512 a, 512 b (and512 c) “virtually” intersect at, and therefore define, an axis ofrotation about an x-axis associated with the row-bar 206. Statedotherwise, the WA flexures 512 a, 512 b (and 512 c) are positioned suchthat if they were to extend through and beyond the back wall 506 and thefront side 504 of box structure 502, they would all intersect at a pointthat defines an axis of rotation (in the x-direction). It is this axisof rotation about which a torque is applied to a head slider (e.g., 208a-208 m of FIG. 2) by way of actuating a corresponding force pin 505,and thus about which the box structure 502 effectively rotates. Recallthat the torque, when transferred through the compliant elastomer 516,manifests as a pressure gradient 904 a applied across the length(y-direction) of the corresponding head slider. Hence, it is thisindependently and variably applied pressure gradient 904 a that providesthe WA lapping control (depicted as block arrow 702) about the commonaxis of rotation for each respective head slider. Because the axis ofrotation is, according to an embodiment, designed to be at or near thecentroid of and at the lapping interface/bottom face of the row-bar 206,precise, independent and dynamically variable (i.e., by varying theactuation of force pins 505) wedge angle control is provided for eachhead slider constituent to row-bar 206.

FIGS. 7 and 7A further illustrate a stripe height (SH) lapping control(depicted as block arrow 704), a use of which is described in referenceto a method of lapping a row-bar in FIG. 8.

Method for Lapping a Row-Bar of Magnetic Read-Write Head Sliders

FIG. 8 is a flow diagram illustrating a method for lapping a row-bar ofhead sliders, according to an embodiment. The various embodimentsdescribed in reference to FIG. 8 may each be performed using the lappingtool 500 (FIGS. 5-7) described elsewhere herein. For context and asdescribed, each row-bar has an x-axis along the direction of the row anda y-axis along the direction of a reader-writer offset associated withthe head sliders in the row-bar, and each head slider comprises a readerelement and a writer element.

At block 802, a row-bar of magnetic read-write head sliders is fixed toa lapping tool fixture. For example, row-bar 206 (FIGS. 5, 6, 7A) isaffixed to fixture 508 (FIGS. 5-7A) of lapping tool 500 (FIGS. 5-7),such as via the elastomer 516 (FIGS. 5, 6, 7A). The tackiness of theelastomer 516 material has an effect on the capability of the elastomer516 to hold the row-bar 206 in place on the fixture 508. Therefore, thetackiness of the elastomer 516 may vary from implementation toimplementation.

At block 804, each of a plurality of force pins of the lapping tool isactuated to set each head slider of the row-bar for lapping to arespective target wedge angle. For example, each force pin 505 isactuated (for non-limiting examples, pneumatically, hydraulically,mechanically, electrically, and the like) to set each head slider 208a-208 m (FIG. 2) of the row-bar 206 to a respective target wedge angle303 (FIG. 3), which is an angle relative to a y-plane along the y-axis.The manner in which each respective target wedge angle is set isconsistent with as described herein in reference to FIGS. 5-7A.

Thus, at block 806, each head slider is simultaneously lapped accordingto each respective corresponding target wedge angle. For example, eachhead slider 208 a-208 m of the row-bar 206 is lapped according to eachcorresponding target wedge angle 303. Recall from FIG. 3 that lappingmay be performed on a head slider or a row-bar of head sliders using alapping fixture 304 and a lapping plate 306, which is commonlydiamond-encrusted and/or accompanied by a diamond slurry.

FIGS. 9A, 9B are diagrams illustrating a “soft” bond WA lapping process,according to an embodiment. Reference is further made to FIGS. 4A, 4Bfor a comparison of the soft bond WA lapping process of FIGS. 9A, 9Bwith the rigid bond WA lapping process of FIGS. 4A, 4B. FIG. 9A depictsa series of “snapshots” (with each snapshot separated by a verticaldashed line) of a “fine lap” (or “final lap”) WAL process, in which anunfinished head slider 902 is temporarily bonded to a rigid toolingfixture 508 by way of a compliant elastomer 516. At the first snapshot,it is appreciated that a proper pressure gradient 904 a for applicationto the head slider 902 to at least begin to achieve the target wedgeangle is determined. For slider 902, a corresponding force pin 505(FIGS. 5-6) is actuated to apply a torque to the lapping tool fixture508 and through the elastomer 516 to the head slider 902 to generate thedesired pressure gradient 904 a across the length of the head slider902. Note that the diagram of FIG. 9A is simplified in that theelastomer 516 appears with sharp lines at its interface with the headslider 902, e.g., as if a portion of elastomer 516 is cut away. However,appreciate that the elastomer 516 will compress (rather than cut out) inresponse to the torque, whereby the torque will cause greatercompression within the elastomer 516 relative to the distance away fromthe axis of rotation (or center of torque) in the direction of thetorque. Likewise, the torque will cause lesser compression within theelastomer 516 relative to the distance away from the axis of rotation(or center of torque) in the direction opposing the direction of thetorque. Hence, pressure gradient 904 a is depicted as smaller to largerin the direction from the left to the right. Consequently, withprogressively larger point pressures applied to the head slider 902across its length (due to the pressure gradient 904 a), and in view ofthe head slider interfacing with a rigid lapping plate 406, morematerial is removed from the slider according to the pressure gradient904 a (i.e., from the left to the right).

With reference to FIG. 9B, it is appreciated that with application ofpressure gradient 904 a to the head slider 902, the progression of headslider 902 material removal is not at a constant angle as lappingprogresses through the WAL process. Because there is some pressureacross the entire length of the slider, albeit varying pressureaccording to the pressure gradient 904 a, the progression of materialremoval is different from that with a rigid bond and constant lappingangle, as depicted in FIG. 4B. With application of the pressure gradient904 a, the lapping angle changes as material is progressively removedfrom the face of head slider 902, as depicted in FIG. 9B.

At the second (middle) snapshot, it is depicted that a slightlydifferent pressure gradient 904 b is applied to the head slider 902 tocontinue to achieve the target wedge angle, such as by way of a servocontrol change as the target wedge angle is approached. Hence, a lappingsystem and method as described herein provides for dynamically changingthe wedge angle, per head slider, with a controlled feedback system(e.g., an ELG feedback system). The wedge angle may be dynamicallychanged by changing the force pin 505 actuation profile during thelapping process, whereby the lapping system is dynamically served toachieve a desired result. It is noteworthy that the use of progressivelychanging wedge angles due to the application of a pressure gradientusing an elastomer, rather than the use of a constant rigid wedge angle,is much less likely to produce a facet(s) in the head slider.

Returning to the flow diagram of FIG. 8, at optional block 808, each ofthe plurality of force pins is actuated to set each head slider of therow-bar for lapping to a respective reader target stripe height. Forexample, each force pin 505 is servo or discretely actuated (fornon-limiting examples, pneumatically, hydraulically, mechanically,electrically, and the like) to set each head slider 208 a-208 m (FIG. 2)of the row-bar 206 to a respective reader target stripe height 215(FIGS. 2A, 3).

Continuing, at optional block 810, each head slider is simultaneouslylapped according to each respective corresponding target stripe height.For example, each head slider 208 a-208 m of the row-bar 206 is lappedaccording to each corresponding reader 214 target stripe height 215(which may be based on a reader ELG and/or writer ELG stripe height).Returning to FIG. 9A, at the third snapshot it is depicted that thetorque and resultant pressure gradient(s) 904 a (and 904 b) across thehead slider is discontinued (e.g., the target wedge angle has beenreached), and a relatively (or “substantially”) constant pressure 904 cacross the length of head slider 902 is now applied, to now lap to thetarget reader 214 stripe height 215.

Thus, according to an embodiment and as described elsewhere herein, incontrast with the rigid bond (rough) lapping process depicted in FIGS.4A, 4B, this soft (fine) lap WAL process first laps to a target wedgeangle and then laps to a target reader or writer stripe height, therebyproviding multiple degrees of control, including control of the RWO(such as RWO 217 of FIG. 2). Compensating the process to first laptoward the target stripe height and then lap to the target wedge angleis also contemplated and within the scope of embodiments describedherein.

Lapping Mount Tool for within-Row Stripe Height/Flare Point and WedgeAngle Lapping

FIG. 10A is a front side perspective view illustrating a lapping mounttool, FIG. 10B is a front top perspective view illustrating the lappingtool of FIG. 10A, and FIG. 10C is a bottom side perspective viewillustrating the lapping tool of FIG. 10A, all according to anembodiment. Unless otherwise noted, many of the functional andoperational concepts described in the context of lapping tool 500 areequally applicable to the lapping mount tool 1000 of FIGS. 10A-10C.

Lapping mount tool 1000 comprises a first structural member 1002 that,according to an embodiment, is rotatable and/or flexible. The firststructural member 1002 houses a plurality of angular actuation pins1005, each of which comprises a V-shaped notch (“V-notch”), or fork 1003(for a non-limiting example, a two-tine fork), at the top at least inpart for actuation purposes. Note that the first and last “pin”structures of the first structural member 1002 are structurallydifferent from and depicted as wider than the inner angular actuationpins 1005, and mainly serve to protect the inner more fragile angularactuation pins 1005, according to an embodiment. However, the lappingmount tool 1000 would still be operable for its intended purpose if thefirst and last “pins” of the first structural member 1002 were to beleft out of the tool, as they are not intended to interact with acorresponding head slider as are the bulk of the angular actuation pins1005. According to an embodiment and as depicted, adjacent forks 1003(e.g., a comb of forks) may be alternatingly staggered in thez-direction, which facilitates engagement between the actuationmechanisms and the corresponding forks 1003 in such a space-limitedenvironment. However, the group of forks 1003 may be configured in linerather than staggered as depicted, according to an embodiment. The firststructural member 1002 comprises a fixture 1008 for holding a row-bar ofmagnetic read-write head sliders (e.g., row 206 a-206 n of FIG. 2;generally, “row-bar 206”), such that each of the plurality of angularactuation pins 1005 is positioned to apply an angular lapping force to acorresponding head slider of the row-bar 206 in response to actuation(e.g., “second actuation”).

The lapping tool 1000 further comprises a second structural member 1006displaced from and coupled with the first structural member 1002 via, orby way of, a first flexible wedge angle (WA) flexure 1012 a (“firstflexure”) and a second flexible wedge angle (WA) flexure 1012 b (“secondflexure”). The second structural member 1006 houses a plurality ofstripe height (SH) actuation pins 1007, each positioned to apply alapping force to a corresponding head slider of the row-bar 206.Similarly to the outer “pin” structures of the first structural member1002, the first and last “pin” structures of the second structuralmember 1006 are structurally different from and depicted as wider thanthe inner SH actuation pins 1007, and mainly serve to protect the innermore fragile SH actuation pins 1007, according to an embodiment.However, the lapping mount tool 1000 would still be operable for itsintended purpose if the first and last “pin” structures of the secondstructural member 1006 were to be left out of the tool, as they are notintended to interact with a corresponding head slider as are the bulk ofthe SH actuation pins 1007. According to an embodiment, each SHactuation pin 1007, in response to actuation (e.g., “first actuation”),applies a substantially z-direction force (see, e.g., linear lappingforce 1105 of FIG. 11) to the corresponding head slider, thereby lappingto a respective target stripe height. According to embodiments, each SHactuation pin 1007 may be actuated to lap to a respective target stripeheight for a reader element of the read-write head or to a respectivetarget stripe height (also, “flare point 213” of FIG. 2A) for a writerelement of the read-write head.

The lapping tool 1000 further comprises a third structural member 1010coupled with the second structural member 1006 via, or by way of, athird flexible flexure 1014 a (“third flexure”) and a fourth flexibleflexure 1014 b (“fourth flexure”).

Notably, the first and second flexures 1012 a, 1012 b “virtually”intersect at, and therefore define, an axis of rotation about an x-axisassociated with the row-bar 206 (depicted and described in more detailin reference to FIG. 11). Hence, in response to actuation (e.g., “secondactuation”), and based on the virtual intersection of the first andsecond flexures 1012 a, 1012 b, each angular actuation pin 1005 appliesan angular lapping force (e.g., a torque) to its corresponding headslider about the axis of rotation defined by the virtual intersection ofthe first and second flexures 1012 a, 1012 b.

Based on the foregoing interacting structures of lapping mount tool1000, an independent and variable stripe height (in the z-axisdirection) can be set for each read-write head of the row-bar 206, forlapping to a respective reader or writer target stripe height (at timesreferred to as the “flare point” for the writer element) by way ofactuating the stripe height actuation pins 1007. Likewise, anindependent and variable wedge angle (relative to the y-axis direction)can be set for each head slider (e.g., head slider 208 a-208 m of FIG.2) of the row-bar 206, for lapping to a respective target wedge angle byway of actuating the angular actuation pins 1005 and according to theeffect of the virtual intersection of the first and second flexures 1012a, 1012 b. In effect, the plurality of angular actuation pins 1005, inresponse to actuation, collectively twists the row-bar 206 toconcurrently set each head slider of the row-bar 206 for concurrentlapping to its respective target wedge angle.

According to an embodiment, the lapping tool 1000 may further comprise acompliant elastomer (such as elastomer 516 of FIG. 5) adhered to thefixture 1008 of the first structural member 1002 and to the row-bar 206,to transfer a y-direction pressure gradient (e.g., pressure gradient 904a of FIG. 9A) corresponding to the angular lapping force from eachangular actuation pin 1005 to the corresponding head slider 208 a-208 m.As such, the material removal associated with each head slider 208 a-208m due to lapping corresponds to the pressure gradient 904 a applied toeach respective head slider 208 a-208 m.

Regarding the compliant elastomer 516, which is employed toattach/adhere the row-bar 206 to angular actuation pins 1005 of thelapping mount tool 1000, the angular change from neighbor angularactuation pins 1005 may induce separation of the elastomer 516 from theangular actuation pins 1005, which may in turn induce separation of therow-bar 206 from the elastomer 516 during lapping. According to anembodiment, the elastomer 516 has a first level of surface roughness onthe side facing the fixture 1008 and a second level of surface roughnessfor the opposing side facing the row-bar 206, where the second level ofsurface roughness is higher than the first level surface roughness.Hence, the effective adhesion forces are less for the higher surfaceroughness (i.e., by reducing the effective contact area) on the row-bar206 side, thereby providing for a more stable row-bar 206 removalprocess (e.g., fewer row-bars are likely to break upon removal from theelastomer 516 after lapping). In contrast, the opposing fixture 1008side of the elastomer 516 is made with a relatively smooth level ofsurface roughness, which maximizes the effective contact area to themount tool pins 1005, 1007 to achieve relatively high levels ofadhesion.

Lapping Mount Tool Wedge Angle Flexures

FIG. 11 is a cross-sectional side view illustrating the lapping tool ofFIGS. 10A-10C, according to an embodiment. FIG. 11 (with reference alsoto FIG. 7A for similar functionality) are referenced to describe in moredetail the operation of the first and second flexures 1012 a, 1012 b.

FIG. 11 illustrates a cross sectional side view of the lapping tool 1000and constituent components, according to embodiments described inreference to FIGS. 10A-10C. FIG. 11 illustrates that the first andsecond flexures 1012 a, 1012 b, which interconnect the rotatable firststructural member 1002 and the second structural member 1006, arepositioned and configured such that the first and second flexures 1012a, 1012 b “virtually” intersect at, and therefore define, an axis ofrotation about an x-axis associated with the row-bar 206. It is thisaxis of rotation about which an angular lapping force 1103 is applied toa head slider (e.g., 208 a-208 m of FIG. 2) by way of actuating 1102 acorresponding angular actuation pin 1005, and thus about which the firststructural member 1102 (e.g., acting as a lever) and associated fixture1008 effectively rotate. Recall that the angular lapping force 1103 (ortorque), when transferred through the compliant elastomer 516, manifestsas a pressure gradient 904 a (FIG. 9) applied across the length(y-direction) of the corresponding head slider. Hence, it is thisindependently and variably applied pressure gradient 904 a that providesthe WA lapping control (e.g., depicted as block arrow for lapping force1103) about the common axis of rotation for each respective head slider.Because the axis of rotation is, according to an embodiment, designed tobe at or near the centroid of and at the lapping interface/bottom faceof the row-bar 206, precise, independent and dynamically variable (i.e.,by varying the actuation 1102 of angular actuation pins 1005) wedgeangle control is provided for each head slider constituent to row-bar206.

FIG. 11 further illustrates that the stripe height actuation pins 1007are positioned and configured such that a linear lapping force 1105(e.g., depicted as block arrow for linear force 1105) is applied to ahead slider (e.g., 208 a-208 m of FIG. 2) by way of actuating 1104 acorresponding stripe height actuation pin 1007. Hence, precise,independent and dynamically variable (i.e., by varying the actuation1104 of angular actuation pins 1007) stripe height/flare point controlis provided for each head slider constituent to row-bar 206.

Drop-Shock Proof Features

As lapping mount tool 1000 may be implemented for uses/operations inwhich the lapping mount tool 1000 is handled, such as moved around amanufacturing site and possibly among different tools (e.g., by anoperator or robotic machine), the effect of drop-shocks/impacts upon thelapping mount tool 1000 is a consideration, keeping in mind that thevarious actuation pins 1005, 1007 may be relatively thin and fragilecomponents. Thus, with reference back to FIG. 11 and according to anembodiment, one or more gap control measures, which function to limitdisplacement, may be incorporated into the configuration of lappingmount tool 1000, for providing some structural spatial tolerance betweencomponents of the lapping mount tool 1000. According to an embodiment, agap 1107 is provided between a terminal portion of the stripe heightactuation pins 1007 of the second structural member 1006 and the surface1106 a of a notch 1106 located toward a distal side of the firststructural member 1002. According to an embodiment, a gap 1108 isprovided between a distal terminal portion of the second structuralmember 1006, to which the second flexure 1112 b is attached, and anopposing proximal surface 1010 a of the third structural member 1010,and/or a gap 1109 is provided between a distal terminal portion of thesecond structural member 1006 and an opposing proximal surface 1010 b ofthe third structural member 1010. The number of drop-shock gapsimplemented may vary from implementation to implementation, as any oneor more of the gaps 1107, 1108, 1109 may be implemented to providedrop-shock protection to the lapping mount tool 1000. In particular, theforegoing multi-direction gap measures are capable of reducing theeffect of a shock/impact event upon the lapping mount tool 1000primarily in the y-direction (e.g., gaps 1108, 1109) but also in thez-direction (e.g., gap 1107).

Furthermore, at least in part due to the combined mass of the firststructural member 1002 (including the angular actuation pins 1005), thestripe height actuation pins 1007, and the primary supporting structureof the second structural member 1006 for the stripe height actuationpins 1007, drop testing in the y-direction has shown a tendency toinduce buckling in the third and fourth flexures 1014 a, 1014 binterconnecting the second structural member 1006 and the thirdstructural member 1010. Hence, according to an embodiment, the third andfourth flexures 1014 a, 1014 b may be implemented as curved flexurebeams (curved along the y-direction, such as depicted in FIG. 11) toinhibit or prevent the buckling mode of these flexures by effectivelyreducing or relaxing the maximum stress imparted to the third and fourthflexures 1014 a, 1014 b upon a shock/impact event. Utilization of suchcurved flexure beams may be implemented with and may function further inconjunction with the foregoing gap measures.

As discussed, the lapping mount tool 1000 may be implemented foruses/operations in which the lapping mount tool 1000 is handled, such astransported around a manufacturing site and possibly among differenttools, so the effect of drop-shocks/impacts upon the lapping mount tool1000 is a consideration. More particularly, according to an embodiment,the lapping mount tool 1000 is conjoined with one or more structuralhousing interconnects to house the lapping mount tool 1000 as well as tointerconnect the mount tool 1000 to other components, higher-levellapping tools and/or fixtures, thus providing a lapping tool assembly,which may be handled and transported around a manufacturing site andpossibly among different tools.

FIG. 12A is an exploded top side perspective view illustrating a portionof a lapping tool assembly, and FIG. 12B is a top side perspective viewillustrating a portion of the lapping tool assembly of FIG. 12A,according to an embodiment. Lapping tool assembly 1200 comprises thelapping mount tool 1000 conjoined with or coupled to an assembly basepart 1202 (“assembly base 1202”). Assembly base 1202 comprises aplurality of interlocking pins 1202 a (e.g., a “comb”). Each adjacentinterlocking pin 1202 a, when engaged with the lapping mount tool 1000,is positioned within a corresponding pocket 1007 a associated with agroup of adjacent stripe height actuation pins 1007 (see, e.g., dashedcircles of FIG. 12B). Hence, engagement of the pins 1202 a of theassembly base 1202 with the lapping mount tool 1000 thereby functions tolimit displacement and material stress of the stripe height actuationpins 1007, primarily in the x-direction (as depicted by arrow 1203 ofFIG. 12A), but also in the z-direction resulting from the structuralconfiguration and shape of the pockets 1007 a. Thus, the stripe heightactuation pins 1007 may be protected from damage (which may affect mounttool accuracy and performance) upon the lapping tool assembly 1200 beingdropped in the direction of arrow 1203, generally, and/or experiencing adrop-shock/impact having a force component in the direction of arrow1203.

FIG. 13A is an exploded front side perspective view illustrating aportion of a lapping tool assembly, and FIG. 13B is an exploded sideperspective view illustrating a portion of the lapping tool assembly ofFIG. 13A, according to an embodiment. Lapping tool assembly 1300comprises the lapping mount tool 1000 conjoined with or coupled to amounting plate part 1302 (“mounting plate 1302”), to which a PCB may bemounted according to an embodiment. Mounting plate 1302 comprises aplurality of lower interlocking pins 1302 a (or a “lower comb”). Eachadjacent lower interlocking pin 1302 a, when engaged with the lappingmount tool 1000, is positioned within a corresponding pocket 1005 aassociated with a group of adjacent angular actuation pins 1005.According to an embodiment, mounting plate 1302 further comprises aplurality of upper interlocking pins 1302 b or “upper comb”), where eachadjacent upper interlocking pin 1302 b, when engaged with the lappingmount tool 1000, is positioned between corresponding adjacent forks 1003or group of forks 1003 constituent to angular actuation pins 1005.Hence, engagement of the lower and upper interlocking pins 1302 a, 1302b of the mounting plate 1302 with the lapping mount tool 1000 therebyfunctions to limit displacement and material stress of the angularactuation pins 1005, primarily in the x-direction (as depicted by arrow1303 of FIG. 12A), but also in the z-direction resulting from thestructural configuration and shape of the pockets 1005 a and from theinterlocking of the upper interlocking pins 1302 a, 1302 b with thecorresponding comb of forks 1003, as well as to ensure proper alignmentwith the actuating mechanisms in the case of the upper interlocking pins1302 a, 1302 b interlocking with the corresponding comb of forks 1003.Thus, the angular actuation pins 1005 may be protected from damage(which may affect mount tool accuracy and performance) upon the lappingtool assembly 1300 being dropped in the direction of arrow 1303,generally, and/or experiencing a drop-shock/impact having a forcecomponent in the direction of arrow 1303.

While the lower and/or upper pins 1302 a, 1302 b of the mounting plate1302 may be implemented independent of the pins 1202 a (FIGS. 12A, 12B)of the assembly base 1202 (FIGS. 12A, 12B), note that the pins 1202 a(FIGS. 12A, 12B) of the assembly base 1202 (FIGS. 12A, 12B) may beimplemented in conjunction with the lower and/or upper pins 1302 a, 1302b of the mounting plate 1302, to provide protection againstdrop-shock/impact damage to both the actuation pins 1007 and the angularactuation pins 1005 of lapping mount tool 1000. Note also thatbuttressing the actuation pins 1005, 1007 with the corresponding pins1302 a, 1302 b, 1202 a may further provide support and protectionagainst damage in the y-direction in the event of a drop-shock or otherimpact event.

Method for Lapping a Row-Bar of Magnetic Read-Write Head Sliders

FIG. 14 is a flow diagram illustrating a method for lapping a row-bar ofhead sliders, according to an embodiment. The various embodimentsdescribed in reference to FIG. 14 may each be performed using thelapping mount tool 1000 (FIGS. 10A-11) described elsewhere herein. Forcontext and as described, each row-bar has an x-axis along the directionof the row and a y-axis along the direction of a reader-writer offsetassociated with the head sliders in the row-bar, and each head slidercomprises a reader element and a writer element.

At block 1402, a row-bar of magnetic read-write head sliders is affixedto a lapping mount tool fixture. For example, row-bar 206 (FIGS. 5, 6,7A) is affixed to fixture 1008 (FIGS. 10A-11) of the first structuralmember 1002 (FIGS. 10A-10C) of the lapping tool 1000 (FIGS. 10A-11),such as via the elastomer 516 (FIGS. 5, 6, 7A), and electricallyconnected to a PCB mounted to mounting plate 1302 (FIGS. 13A, 13B).

At block 1404, each of a plurality of first actuation pins of thelapping mount tool is actuated thereby setting each head slider of therow-bar for lapping to a respective target stripe height (stripe heightmay at times referred to as flare point for a writer element). Forexample, each stripe height actuation pin 1007 (FIGS. 10A-11) isactuated 1104 (FIG. 11) (for non-limiting examples, pneumatically,hydraulically, mechanically, electrically, and the like) to set eachhead slider 208 a-208 m (FIG. 2) of the row-bar 206 for lapping to arespective target reader stripe height 215 (FIG. 2A), which is adimension relative to the z-axis direction. The manner in which eachrespective target stripe height is set is consistent with as describedherein in reference to FIGS. 10A-11.

Thus, at block 1406, each head slider is simultaneously lapped accordingto each respective corresponding target stripe height. For example, eachhead slider 208 a-208 m of the row-bar 206 is lapped according to eachcorresponding target stripe height 215 in response to a respectivelinear lapping force 1105 (FIG. 11). Recall from FIG. 3 that lapping maybe performed on a head slider or a row-bar of head sliders using alapping fixture 304 and a lapping plate 306, which is commonlydiamond-encrusted and/or accompanied by a diamond slurry.

Continuing on with wedge angle lapping if applicable or desired, atblock 1408, each of a plurality of second actuation pins of the lappingmount tool is actuated thereby setting each head slider of the row-barfor lapping to a respective target wedge angle. For example, eachangular actuation pin 1005 (FIGS. 10A-11) is actuated 1102 (FIG. 11)(for non-limiting examples, pneumatically, hydraulically, mechanically,electrically, and the like) to set each head slider 208 a-208 m of therow-bar 206 for lapping to a respective target wedge angle 303 (FIG. 3),which is an angle relative to the y-axis direction. The manner in whicheach respective target wedge angle is set is consistent with asdescribed herein in reference to FIGS. 10A-11. Recall that each angularactuation pin 1005 is housed within the first structural member 1002(FIGS. 10A-10C) of the lapping mount tool 1000 and, based on the virtualintersection of the first flexure 1012 a (FIGS. 10A, 10C, 11) and thesecond flexure 1012 b (FIGS. 10A, 10C, 11) that interconnect the firststructural member 1002 with the second structural member 1006, wheresuch virtual intersection defines the axis of rotation of the angularactuation pins 1005 (and thus the row-bar 206) about the x-axis, appliesan angular lapping force 1103 (FIG. 11) through each angular actuationpin 1005 to a corresponding head slider 208 a-208 m about the definedaxis of rotation.

Thus, at block 1410, each head slider is simultaneously lapped accordingto each respective corresponding target wedge angle. For example, eachhead slider 208 a-208 m of the row-bar 206 is lapped according to eachcorresponding target wedge angle 303. Recall from FIG. 3 that lappingmay be performed on a head slider or a row-bar of head sliders using alapping fixture 304 and a lapping plate 306, which is commonlydiamond-encrusted and/or accompanied by a diamond slurry. According toan embodiment, actuating 1102 the second actuation pins at block 1408 isperformed after actuating 1104 the first actuation pins at block 1404.However, this order of activities may vary from implementation toimplementation and, therefore, may be reversed if desired.

Lapping Tool Assembly with Tilt Interposer

FIG. 15A is a side perspective view illustrating a lapping tool assemblyincluding a tilt interposer, and FIG. 15B is a side perspective viewillustrating a portion of the lapping tool assembly of FIG. 15A,according to embodiments. FIG. 16 is a cross-sectional side view of thetilt interposer of FIG. 15A, and FIG. 17 is a cross-sectional side viewof the lapping tool assembly of FIG. 15A, according to embodiments.Lapping tool assembly 1500 is an assembly comprising the lapping mounttool 1000 (see FIGS. 10A-11), a plurality of actuators 1510 (for anon-limiting example, air bearing actuators) for actuating the angularactuation pins 1005 of the mount tool 1000, and an actuation interposer1502 (“interposer 1502”) interposed between the actuators 1510 and themount tool 1000.

The interposer 1502 structure comprises a first element comprising aplurality of interposer structures 1504 (“interposer pins 1504” or,collectively, “first element 1504”), each reactively coupled with acorresponding actuator 1510. Each interposer pin 1504 is configured toreceive a respective translational force 1511 from the correspondingactuator 1510 for transmission or application to a corresponding angularactuation pin 1005 of mount tool 1000. The interposer 1502 furthercomprises a second element, a T-shaped structure 1506 (“T-structure1506”) that is coupled (a) to the first element 1504 via a first flexure1505 a and a second flexure 1505 b and (b) to a fixed frame or housing1508 via a third flexure 1507 a and a fourth flexure 1507 b. Refer toFIG. 16 for an illustration of the foregoing flexure system (flexuresnot shown in FIG. 15A to maintain clarity), which may be characterizedas a zero z-axis (vertical) shift flexure system.

In view of the first element 1504 “hanging” from the T-structure 1506 bythe flexible first and second flexures 1505 a, 1505 b, when actuated inthe horizontal (y-axis) direction, the first element 1504 has a naturaltendency to swing or arc upward in a counterclockwise direction, e.g.,through bending of the first and second flexures 1505 a, 1505 b. Anyupward motion (z-axis) of the first element 1504 is undesirable becausea simple linear translation of the first element 1504 in the y-directionis preferred, in order to properly engage with and to translate theactuation forces substantially normal to the receiving angular actuationpins 1005 of the mount tool 1000. Thus, according to an embodiment, thefirst flexure 1505 a, the second flexure 1505 b, the third flexure 1507a, and the fourth flexure 1507 b are configured (e.g., as depicted inFIG. 16) such that the tendency of the first element to swing upward ina counterclockwise direction is offset by the T-structure 1506 swingingdownward in a clockwise direction through bending of the third andfourth flexures 1507 a, 1507 b. Consequently, the interposer pins 1504constituent to the first element are allowed or forced to translatesubstantially linearly in the y-direction only.

With reference to FIG. 16, according to an embodiment the first element1504 further comprises an interposer-to-mount tool z-axis decoupler ordecoupling flexure system, wherein each interposer pin 1504 of the firstelement of the interposer 1502 comprises (a) a proximal end 1504 aproximal to the actuators 1510, (b) a distal end 1504 c including a tip1504 e engageable with the corresponding angular actuation pin 1505 ofthe mount tool 1000, and (c) an intermediate structure 1504 b betweenthe proximal end 1504 a and the distal end 1504 c, from which the distalend 1504 c extends. The z-axis decoupling flexure system embodied in thefirst element 1504 further comprises a group of one or more firstdecoupler flexures 1504 f and a group of one or more second decouplerflexures 1504 f, which couple the proximal end 1504 a to theintermediate structure 1504 b. The structural configuration of the firstand second decoupler flexures 1504 f may vary from implementation toimplementation. For non-limiting examples, each of the first and thesecond decoupler flexures 1504 f may comprise a single flexure 1504 fcorresponding to each interposer pin 1504 and spanning between theproximal end 1504 a to the intermediate structure 1504 b, or each maycomprise a monolithic flexure 1504 f spanning the proximal end 1504 a tothe intermediate structure 1504 b.

Implementation of the first and second flexures 1504 f provides areduced or relatively low bending stiffness for this portion of thefirst element 1504, thereby allowing each distal end 1504 c to followthe corresponding engaged angular actuation pin 1005 of the mount tool1000 while substantially decoupling the influence of forces from eachdistal end 1504 c upon the mount tool 1000. More specifically, recallthat the angular actuation pins 1005 and the stripe height actuationpins 1007 (which move in the z-axis direction for lapping) of the mounttool 1000 are coupled via the first flexure 1012 a and the secondflexure 1012 b of the mount tool 1000 (see, e.g., FIGS. 10A, 10C, 11)and, therefore, movement of one type of actuation pin may influence theother type of actuation pin. However, the foregoing z-axis decouplerflexure system operates to substantially decouple the application ofy-axis direction engagement forces from the interposer pins 1504 (e.g.,due to the direct engagement of the respective tip 1504 e of eachinterposer pins 1504 with the angular actuation pins 1005) to the stripeheight actuation pins 1007, thereby inhibiting or reducing oreliminating such y-axis forces from affecting the stripe heightactuation pins 1007 in the z-axis direction.

FIG. 18 is a side perspective view of a pre-aligner of the actuator tiltinterposer of FIG. 15A, according to an embodiment. With reference nowto FIG. 16 and FIG. 18, according to an embodiment each interposer pin1504 is depicted as comprising an alignment bump structure/feature 1504d (“alignment bump 1504 d”) that helps aligns the corresponding distalend 1504 c of the interposer pin 1504 with the corresponding angularactuation pin 1005 of the mount tool 1000. Stated otherwise, eachalignment bump 1504 d substantially centers the corresponding distal endtip 1504 e of an interposer pin 1504 within a fork 1003 of acorresponding angular actuation pin 1005 when the interposer pin 1504 isengaged with the angular actuation pin 1005.

With reference to FIGS. 15A, 15B, 17, and 18, the lapping tool assembly1500 further comprises a pre-aligner comb 1512 that positions eachinterposer pin 1504 within a certain z-axis (vertical) tolerance range.That is, the pre-aligner comb 1512 operates to constrain the interposerpins 1504 in the z-axis direction. Furthermore, once the interposer pins1504 are properly and securely engaged with the corresponding angularaction pins 1005 of the mount tool 1000, each alignment bump 1504 d ofthe interposer pins 1504 is positioned between the pre-aligner comb 1512and the distal end tip 1504 e of the interposer pin 1504. Hence, eachinterposer pin 1504 is free to move in the z-axis direction, once eachalignment bump 1504 d is located outside of the pre-aligner comb 1512,along with the respective engaged angular actuation pin 1005 of themount tool 1000.

Method for Applying Actuation Forces to a Lapping Mount Tool for LappingA Row-Bar of Magnetic Sensor Devices

FIG. 19 is a flow diagram illustrating a method for applying actuationforces to a lapping mount tool for lapping a row-bar of magnetic sensordevices, according to an embodiment, where the row-bar has an x-axisalong the direction of the row and a y-axis along the direction of thewidth of the row-bar. Magnetic sensor devices may include, for example,any of a myriad of forms of magnetic read-write heads, or magneticreaders alone, or other types of magnetic sensors, generally.

At block 1902, the row-bar is affixed to a lapping mount tool fixture.For example, row-bar 206 (FIGS. 5, 6, 7A) is affixed to fixture 1008(FIGS. 10A-11) of the first structural member 1002 (FIGS. 10A-10C) ofthe lapping tool 1000 (FIGS. 10A-11), such as via the elastomer 516(FIGS. 5, 6, 7A).

At block 1904, each of a plurality of actuators is actuated to apply arespective translational force from each actuator to a correspondinginterposer pin of an interposer structure. For example, each of theactuators 1510 (FIGS. 15A, 17) of actuator assembly 1500 (FIGS. 15A,15B, 16, 17) is actuated, to apply a respective translational force 1511(FIGS. 15A, 17) to a corresponding interposer pin 1504 (FIGS. 15A, 16,17) of the interposer structure 1502 (FIGS. 15A, 16, 17).

At block 1906, a zero z-axis shift flexure system is operated, wheresuch a flexure system comprises (a) a set of first flexuresinterconnecting the interposer pins and a rotatable T-structure of theinterposer structure and (b) a set of second flexures interconnectingthe T-structure with a fixed frame, such that a tendency of theinterposer pins to swing upward counterclockwise upon actuation, due tobending of the first flexures, is offset by the T-structure swingingdownward clockwise, due to bending of the second flexures, such that theinterposer pins translate substantially in the y-direction only. Forexample, the mechanism of interposer structure 1502 (FIG. 16) isoperated, where such mechanism comprises (a) the set of first flexures1507 a interconnecting the interposer pins 1504 and the rotatableT-structure 1506 ((FIGS. 15A, 16, 17) of the interposer structure 1502and (b) the set of second flexures 1507 b interconnecting theT-structure 1506 with a fixed frame 1508 (FIGS. 15A, 16, 17), such thata tendency of the interposer pins 1504 to swing upward counterclockwiseupon actuation, due to bending of the first flexures 1507 a, is offsetby the T-structure 1506 swinging downward clockwise, due to bending ofthe second flexures 1507 b, such that the interposer pins 1504 translatesubstantially in the y-direction only.

According to an embodiment, at optional block 1908, aninterposer-to-mount tool z-axis decoupling flexure system is operated,where such a flexure system comprises a set of one or more firstdecoupling flexures and a set of one or more second decoupling flexuresthat couple each proximal end to an intermediate structure of theinterposer pins, such that the application of the y-direction forcesfrom the interposer pins to the lapping mount tool are substantiallydecoupled from the z-axis direction. For example, an interposer-to-mounttool z-axis decoupling flexure system is operated, where such a flexuresystem comprises a set of one or more first decoupling flexures 1504 f(FIG. 16) and a set of one or more second decoupling flexures 1504 f(FIG. 16) that couple each proximal end 1504 a (FIG. 16) to anintermediate structure 1504 b (FIG. 16) of the interposer pins 1504,such that the application of the y-direction forces from the interposerpins 1504 to the lapping mount tool 1000 are substantially decoupledfrom the z-axis direction.

According to an embodiment, at optional block 1910, a respectivealignment bump near the distal end of each interposer pin is allowed tosubstantially center a distal end tip of the interposer pin within aV-notch of a corresponding actuation pin of the lapping mount tool insituations in which the interposer pin is engaged with the actuationpin. For example, the respective alignment bump 1504 d (FIGS. 16, 18)near the distal end 1504 c (FIG. 16) of each interposer pin 1504 isallowed to substantially center the distal end tip 1504 e (FIGS. 16, 18)of the interposer pin within the fork 1003 (FIGS. 10A-10C, 18) of acorresponding angular actuation pin 1005 (FIGS. 10A-10C, 15A, 15B, 17,18) of the lapping mount tool 1000 in situations in which the interposerpin 1504 is engaged with the angular actuation pin 1005.

According to an embodiment, at optional block 1912, a pre-alignment combis allowed to position each interposer pin within a z-axis tolerancerange, where each alignment bump of the interposer pin is positionedbetween the pre-alignment comb and the distal end tip of the interposerpin such that the interposer pin is free to move in the z-axisdirection, with the z-axis tolerance range, with the respective engagedactuation pin of the lapping mount tool. For example, the pre-alignmentcomb 1512 (FIGS. 15A, 15B, 17, 18) is allowed to position eachinterposer pin 1504 within a z-axis tolerance range, where eachalignment bump 1504 d of the interposer pin 1504 is positioned betweenthe pre-alignment comb 1512 and the distal end tip 1504 e of theinterposer pin 1504 such that the interposer pin 1504 is free to move inthe z-axis direction, within the z-axis tolerance range, with therespective engaged angular actuation pin 1005 of the lapping mount tool1000.

Extensions and Alternatives

In the foregoing description, embodiments of the invention have beendescribed with reference to numerous specific details that may vary fromimplementation to implementation. Therefore, various modifications andchanges may be made thereto without departing from the broader spiritand scope of the embodiments. Thus, the sole and exclusive indicator ofwhat is the invention, and is intended by the applicants to be theinvention, is the set of claims that issue from this application, in thespecific form in which such claims issue, including any subsequentcorrection. Any definitions expressly set forth herein for termscontained in such claims shall govern the meaning of such terms as usedin the claims. Hence, no limitation, element, property, feature,advantage or attribute that is not expressly recited in a claim shouldlimit the scope of such claim in any way. The specification and drawingsare, accordingly, to be regarded in an illustrative rather than arestrictive sense.

In addition, in this description certain process steps may be set forthin a particular order, and alphabetic and alphanumeric labels may beused to identify certain steps. Unless specifically stated in thedescription, embodiments are not necessarily limited to any particularorder of carrying out such steps. In particular, the labels are usedmerely for convenient identification of steps, and are not intended tospecify or require a particular order of carrying out such steps.

What is claimed is:
 1. A lapping tool assembly comprising: a mount toolcomprising: a rotatable first structural member housing a plurality ofangular actuation pins each positioned to apply an angular lapping forceto a corresponding head slider of a row-bar of magnetic read-write headsliders, said first structural member comprising a fixture for holdingsaid row-bar, and a second structural member coupled with said firststructural member via a first flexure and a second flexure, said secondstructural member housing a plurality of stripe height actuation pinseach positioned to apply a lapping force to a corresponding head sliderof said row-bar; and an interposer structure interposed between aplurality of actuators and said mount tool, said interposer comprising:a first element comprising a plurality of interposer pins reactivelycoupled with said plurality of actuators such that each said interposerpin is configured to receive a respective translational force from acorresponding said actuator for transmission of said respectivetranslational force to a corresponding said angular actuation pin ofsaid mount tool, and a second element coupled to said first element viaa first flexure and a second flexure, and coupled to a fixed housing viaa third flexure and a fourth flexure.
 2. The lapping tool assembly ofclaim 1, wherein said first, second, third, and fourth flexures areconfigured such that: upon said first element receiving saidtranslational forces in a y-direction from said actuators, a naturaltendency of said first element to swing upward counterclockwise due tobending of said first and second flexures is offset by said secondelement swinging downward clockwise due to bending of said third andfourth flexures, such that said first element translates substantiallylinearly only in the y-direction.
 3. The lapping tool assembly of claim1, wherein: said plurality of stripe height actuation pins, whenactuated, translate substantially in a z-direction; said interposer pinsof said first element of said interposer structure each comprises aproximal end proximal to said actuators, a distal end including a distalend tip engageable with said corresponding angular actuation pin of saidmount tool, and an intermediate structure between said proximal end andsaid distal end and from which said distal end extends; and said firstelement further comprises a decoupler flexure system comprising a groupof one or more first decoupler flexures and a group of one or moresecond decoupler flexures coupling said proximal end to saidintermediate structure of said interposer pins to substantially decoupleapplication of y-direction engagement forces from said interposer pinsto said stripe height actuation pins from affecting said stripe heightactuation pins of said mount tool in said z-direction.
 4. The lappingtool assembly of claim 1, wherein: said interposer pins of said firstelement of said interposer structure each comprises a proximal endproximal to said actuators, a distal end tip engageable with saidcorresponding angular actuation pin of said mount tool, and anintermediate structure between said proximal end and said distal end andfrom which said distal end extends; and said distal end of each saidinterposer pin comprises an alignment bump that substantially centerssaid distal end tip of said interposer pin within a v-notch of saidcorresponding angular actuation pin when said interposer pin is engagedwith said angular actuation pin.
 5. The lapping tool assembly of claim4, further comprising: a pre-aligner comb that positions each interposerpin within a vertical tolerance range; wherein each said alignment bumpof said interposer pin is positioned between said pre-aligner comb andsaid distal end tip of said interposer pin such that said interposer pinis free to move in the z-direction with the respective engaged angularactuation pin of the mount tool.
 6. A lapping tool actuation interposercomprising: a first element comprising a plurality of interposer pinsreactively coupled with a plurality of actuators such that each saidinterposer pin is configured to receive a respective translational forcefrom a corresponding said actuator for transmission of said respectivetranslational force to a corresponding lapping mount tool angularactuation pin; and a second element coupled to said first element via afirst flexure and a second flexure, and coupled to a fixed frame via athird flexure and a fourth flexure.
 7. The actuation interposer of claim6, wherein said first, second, third, and fourth flexures aresubstantially parallel in a static state and are configured such that:upon said first element receiving said translational forces in ay-direction from said actuators, a natural tendency of said firstelement to swing upward counterclockwise due to bending of said firstand second flexures is offset by said second element swinging downwardclockwise due to bending of said third and fourth flexures, such thatsaid first element translates substantially linearly only in they-direction.
 8. The actuation interposer of claim 6, wherein: saidlapping mount tool further comprises a plurality of stripe heightactuation pins which when actuated translate substantially in az-direction, and said stripe height actuation pins are mechanicallycoupled to said angular actuation pins such that upon said first elementtransmitting said translational forces in a y-direction to said angularactuation pins, said angular actuation pins rotate and tend to affectsaid stripe height actuation pins in said z-direction; said interposerpins of said first element each comprises a proximal end proximal tosaid actuators, a distal end including a distal end tip engageable withsaid corresponding angular actuation pin of said mount tool, and anintermediate structure positioned between said proximal end and saiddistal end and from which said distal end extends; and said firstelement further comprises a decoupler flexure system comprising a groupof one or more first decoupler flexures and a group of one or moresecond decoupler flexures coupling said proximal end to saidintermediate structure of said interposer pins to substantially decoupleapplication of y-direction engagement forces from said interposer pinsto said stripe height actuation pins from affecting said stripe heightactuation pins of said mount tool in said z-direction.
 9. The actuationinterposer of claim 6, wherein: said interposer pins of said firstelement each comprises a proximal end proximal to said actuators, adistal end including a distal end tip engageable with said correspondingangular actuation pin of said mount tool, and an intermediate structurebetween said proximal end and said distal end and from which said distalend extends; and said distal end of each said interposer pin comprisesan alignment bump that aligns said interposer pin in said z-directionwith a fork of said corresponding angular actuation pin when saidinterposer pin is engaged with said angular actuation pin.
 10. A methodfor applying actuation forces to a lapping mount tool for lapping arow-bar of magnetic sensor devices, wherein said row-bar has an x-axisalong the direction of the row and a y-axis along the direction of thewidth of said row-bar, the method comprising: affixing said row-bar to alapping mount tool fixture; actuating each of a plurality of actuatorsto apply a respective translational force from each said actuator to acorresponding interposer pin of an interposer structure; operating azero z-axis shift flexure system comprising a set of first flexuresinterconnecting said interposer pins and a rotatable T-structure of saidinterposer structure and a set of second flexures interconnecting saidT-structure with a fixed frame, such that a tendency of said interposerpins to swing upward counterclockwise upon actuation due to bending ofsaid first flexures is offset by said T-structure swinging downwardclockwise due to bending of said second flexures, such that saidinterposer pins translate substantially in the y-axis direction only.11. The method of claim 10, wherein said interposer pins each comprisesa proximal end proximal to said actuators, a distal end including adistal end tip engageable with a corresponding angular actuation pin ofa lapping mount tool, and an intermediate structure between saidproximal end and said distal end and from which said distal end extends,the method further comprising: operating an interposer-to-mount toolz-axis decoupling flexure system comprising a set of one or more firstdecoupling flexures and a set of one or more second decoupling flexuresthat couple said proximal end to said intermediate structure of saidinterposer pins such that application of y-axis direction forces fromsaid interposer pins to said lapping mount tool are substantiallydecoupled from said z-axis direction.
 12. The method of claim 10,wherein said interposer pins each comprises a proximal end proximal tosaid actuators, a distal end including a distal end tip engageable witha corresponding angular actuation pin of a lapping mount tool, and anintermediate structure between said proximal end and said distal end andfrom which said distal end extends, the method further comprising:allowing a respective alignment bump near said said distal end of eachsaid interposer pin to substantially center said distal end tip of saidinterposer pin within a v-notch of a corresponding actuation pin of saidlapping mount tool when said interposer pin is engaged with saidactuation pin.
 13. The method of claim 12, further comprising: allowinga pre-alignment comb to position each interposer pin within a z-axistolerance range; wherein each said alignment bump of said interposer pinis positioned between said pre-alignment comb and said distal end tip ofsaid interposer pin such that said interposer pin is free to move in thez-axis direction, within said z-axis tolerance range, with therespective engaged actuation pin of the lapping mount tool.
 14. Anactuator-to-lapping tool interposer comprising: means for applying azero z-axis shift such that a tendency of interposer pins, housed withinsaid interposer, to swing upward counterclockwise upon y-axis actuationis offset by a T-structure, housed within said interposer, swingingdownward clockwise, such that said interposer pins translatesubstantially in the y-axis direction only.
 15. The actuator-to-lappingtool interposer of claim 14, further comprising: means for applying az-axis decoupling mechanism such that application of y-axis directionforces from said interposer pins to a lapping mount tool aresubstantially decoupled from said z-axis direction.